An incremental neural network for tissue segmentation in ultrasound images

This paper presents an incremental neural network (INeN) for the segmentation of tissues in ultrasound images. The performances of the INeN and the Kohonen network are investigated for ultrasound image segmentation. The elements of the feature vectors are individually formed by using discrete Fourier transform (DFT) and discrete cosine transform (DCT). The training set formed from blocks of 4x4 pixels (regions of interest, ROIs) on five different tissues designated by an expert is used for the training of the Kohonen network. The training set of the INeN is formed from randomly selected ROIs of 4x4 pixels in the image. Performances of both 2D-DFT and 2D-DCT are comparatively examined for the segmentation of ultrasound images.     

Interkulturalität und informatische Gestaltung – Eine interdisziplinäre Annäherung

Zusammenfassung   Dieser Beitrag behandelt - aus einer interdisziplin?ren Perspektive - die Bedeutung der Interkulturalit?t für die Gestaltung in und mit der Informatik im Zeitalter zunehmender Globalisierung. In diesem Zusammenhang wird, um die Rolle der Kultur in der Kommunikation zu verstehen, auf linguistisch-empirische Untersuchungen zur schriftlichen Kommunikation eingegangen und ihre Brauchbarkeit für die Gestaltung hinterfragt. Anschlie?end wird der Frage nach M?glichkeiten und Grenzen des interkulturellen Verstehens und Dialoges in der Philosophie nachgegangen, um daraus Rechtfertigungen für die interkulturelle Orientierung in der Informatik zu erarbeiten. Schlie?lich werden aktuelle informatische Entwicklungen in interkulturellen Kontexten diskutiert. Eingegangen in überarbeiteter Form am 30.04.1998     

Casting properties of ASTM A128 Gr. E1 steel modified with Mn-alloying and titanium ladle treatment

This work aims to produce a high manganese steel with more refined austenite grains and better wear resistance without sacrificing the toughness and tensile properties by Mn alloying and Ti ladle treatment in comparision to ASTM A128 Gr. E1 steel (1.0C-13Mn) that is mostly used in the mining industry. The 1.0C-17Mn-xTi alloys (x=0, 0.05 and 0.1, in wt.%) were prepared. A relationship was established between the microstructures and mechanical properties of the as-cast and solution annealed alloys. Increasing Ti content increases the stable Ti(CN) phase on and beside the grain boundaries and decreases up to 37% the austenite grain size of the as-cast alloy with 0.10wt.% Ti. Correspondingly, after solution annealed, optimized titanium content (0.05wt.%) results in significant improvements in wear resistance, hardness, elongation, yield and tensile strengths by 44%, 31%, 30%, 8% and 12%, respectively, except 9% decrease in impact toughness compared to ASTM A 128 Gr. E1 steel without modification. These results show that 1.0C-17Mn-0.05Ti alloy can be used for parts exposed to high load wear and applied in conditions where relatively high tensile properties with sufficent ductility is needed.

     

Radioactive element contents of some granites used as building materials: insights into the radiological hazards

This study was conducted to investigate the radioactive potential hazard of granite, which is widely used as building material in Turkey. Natural radiation levels of 18 various, globally-distributed industrial granite samples imported by Turkey, were analyzed using gamma-ray spectrometer. The results are compared with the formerly published findings of granite samples from Turkey. Radioactivity levels of ²³⁸U, ²³²Th, and ⁴⁰K natural radioactive series elements of the selected 18 specimens were measured, which were from 2.4 ± 0.5 to 88.8 ± 3.6 Bq kg^?1 for ²³⁸U, from 2.4 ± 0.7 to 273 ± 0.9 Bq kg^?1 for ²³²Th, and from 169 ± 24 to 1,479 ± 94 Bq kg^?1 for ⁴⁰K. Radium equivalent activities (Ra_eq) were calculated for the granite samples to assess their radiation hazards in the construction of dwellings. The Ra_eq values of granite samples varied in the range of 39.05–570 Bq kg^?1, only one sample exceeded the safe limit value of 370 Bq kg^?1 set by the OECD-NEA (Nuclear Energy Agency. Exposure to radiation from natural radioactivity in building materials. Report by NEA Group of Experts 1979). Absorbed dose rates in air were found between 18.74 and 261 nGy h^?1 and radiogenic heat production values were calculated in the range of 0.45–6.53 μW m^?3. All rock samples used in this study were also analysed mineralogically and defined their compositions.     

Immobilization Horseradish Peroxidase onto UiO-66-NH2 for Biodegradation of Organic Dyes

Enzymes are extensively used as catalyst in several fields of production such as chemistry, and pharmaceuticals owing to their selectivity, efficiency and environmentally friendliness. However, their applications are often hindered due to their insufficient stability and difficulties in re-use. As a member of porous crystalline materials, metal organic frameworks are a promising enzyme carrier due to their multi-functional pore surfaces and robustness in variety of harsh conditions. In this study, the horseradish peroxidase (HRP) enzyme was immobilized onto UiO-66-NH₂ (Universitetet i Oslo) by a facile incubation method at the room temperature to improve the stability and reusability of enzyme. The prepared HRP@UiO-66-NH₂ bio-composite was characterized by using FT-IR, XRD and SEM. The crystal structure of MOF was well-preserved after enzyme immobilization. A colorimetric assay for enzyme activity after released from UiO-66-NH₂ has been employed based on the catalytic oxidation of phenol coupled with 4-aminoantipyrine. The robustness and activity of immobilized enzyme after released from UiO-66-NH₂ were investigated by biodegradation of methyl orange (MO) and methylene blue (MB) with several parameters such as pH, temperature, the dosage of H₂O₂ and the dye concentration with comparison to its free form. The optimum condition for dye degradation was obtained at basic conditions. The immobilized enzyme maintained its activity at elevated temperature while free enzyme lost its activity at the same conditions, attributed to the armoring effect of UiO-66-NH₂. According to the results of studied various parameters, MO and MB were biodegraded to 60% and 45%, respectively, within 60 min with the optimum conditions at pH 9 and 50 °C at a H₂O₂ dosage of 3%. The superior pH tolerance and stability suggest potential of UiO-66-NH₂ immobilized peroxidase enzyme in industrial applications.

     

Effect of Ti amount on wear and corrosion properties of Ti-doped Al2O3 nanocomposite ceramic coated CP titanium implant material

Al₂O₃ and Ti-doped Al₂O₃ nanocomposite ceramic coatings were prepared by using a sol-gel dip-coating process. Corrosion and wear resistance of Al₂O₃ ceramic coatings in relation to Ti amount were carried out using pin-on-disk tribotester, potentiodynamic polarization and electrochemical impedance spectroscopy (EIS). Surface characterizations before and after the corrosion and wear tests were investigated by the scanning electron microscope (SEM) and X-ray diffraction (XRD) and hardness analysis. The results of corrosion and wear tests exhibited that the corrosion and wear resistance of nanocomposite ceramic coatings became better than uncoated samples. Also, corrosion and wear resistance of nanocomposite ceramic coatings improved with Ti doping content increased.     

Effects of liquid smoke on quality characteristics of Turkish standard smoked beef tongue

The purpose of this research was to determine some quality characteristics of beef tongues processed with liquid and vaporous (traditional) smoke. The tongues were divided into two groups; traditional (vaporous) smoking and liquid smoke application groups, and the processed tongues were vacuum packaged and monitored for quality during 30 days of storage at 4±1?°C. All the smoked tongue samples were subjected to chemical, microbiological and organoleptic analysis at 0, 5, 10, 15 and 30 days of storage. The results indicated that despite some favorable results attributed to traditional smoking, liquid smoke application of beef tongue is also possible without causing any major acceptability problems in terms of quality.     

Economic evaluation of alternative wastewater treatment plant options for pulp and paper industry

Excessive water consumption in pulp and paper industry results in high amount of wastewater. Pollutant characteristics of the wastewater vary depending on the processes used in production and the quality of paper produced. However, in general, high organic material and suspended solid contents are considered as major pollutants of pulp and paper industry effluents. The major pollutant characteristics of pulp and paper industry effluents in Turkey were surveyed and means of major pollutant concentrations, which were grouped in three different pollution grades (low, moderate and high strength effluents), and flow rates within 3000 to 10,000 m³/day range with 1000 m³/day steps were used as design parameters. Ninety-six treatment plants were designed using twelve flow schemes which were combinations of physical treatment, chemical treatment, aerobic and anaerobic biological processes. Detailed comparative cost analysis which includes investment, operation, maintenance and rehabilitation costs was prepared to determine optimum treatment processes for each pollution grade. The most economic and technically optimal treatment processes were found as extended aeration activated sludge process for low strength effluents, extended aeration activated sludge process or UASB followed by an aeration basin for medium strength effluents, and UASB followed by an aeration basin or UASB followed by the conventional activated sludge process for high strength effluents.